1. Field of the Invention
The present invention relates to a method and a device for checking carry-on luggage and other objects carried by flight passengers during check-in.
2. Description of the Background Art
Many methods and devices are known for inspecting carry-on luggage and other objects that flight passengers carry with them during check-in. Thus, as is well known, x-ray inspection systems for carry-on luggage and metal detectors for scanning people are fixedly installed at airports, to check flight passengers and their carry-on luggage for security-relevant objects such as weapons, explosives, etc.
X-ray inspection systems are also known that permit automatic detection of explosives in closed containers. Thus, German Patent Application No. DE 199 54 662 describes an x-ray inspection system for detecting prohibited objects in items, said system that in a first examination stage determines locations that are analyzed more precisely in a second stage with use of x-ray diffraction. U.S. Pat. No. 5,182,764 discloses an inspection system for pieces of luggage, in which the inspected object is irradiated in a first stage by an x-ray scanner. Its results are used to determine locations that are imaged in a subsequent computed tomography (CT).
Conventional multistage automatic inspection systems are utilized for checking checked-in luggage. Because of the size, high cost, possible low throughput, and high maintenance cost, these systems are less suitable, however, for examining carry-on luggage and objects carried by passengers (e.g., articles of clothing) during a check-in at airports. Increasing the throughput by parallization of several systems is not a realistic option for reasons of space and cost.
Pieces of luggage can be divided into classes of different complexity in regard to inspection by means of x-ray inspection systems. Whereas larger pieces of luggage checked in by the flight passenger predominantly have a very complex content, the complexity of carry-on luggage and other objects carried by a flight passenger varies considerably. Thus, jackets or other outer clothing, typically inspected placed in trays, are less complex and relatively simple to inspect. In the case of carry-on luggage, for example, briefcases, the complexity varies depending on their content. According to experience, carry-on luggage consists of 30%-50% simple and 50%-70% complex objects. This circumstance is utilized according to the invention to reduce the number of items for which a laborious and thereby intensive inspection must be performed.